Usage:
3406B Truck Engines (7FB)
3406B Truck Engines that are equipped with new scroll fuel systems are no longer equipped with governor flyweight shields. Field reports have indicated that the shield can loosen from the flyweight carrier and come into contact with the flyweights and rack control linkages. The purpose of the flyweight shield was to keep any excess oil in the governor housing from splashing against the flyweights. Tests have proven that excess oil does not normally build up in the housing. The flyweight shield was discontinued on production machines, and a field rework program announced.
Many engines have already been reworked. Check the serial number of your engine. If it is in the 7FB1-7FB06809 range, the flyweight shield may not have been removed yet. If you have an engine with an affected serial number and you are not sure if the flyweight shield has been removed, contact the closest Caterpillar dealer. He will inspect the governor housing and quickly tell you if the flyweight shield has been removed. If the flyweight shield has not been removed, a convenient time can be scheduled by the dealer to have this done. The rework takes approximately three hours to complete.